Heteroatoms doped iron oxide-based catalyst prepared from zinc slag for efficient selective catalytic reduction of NO_(x) with NH_(3)

Excessive emissions of nitrogen oxides from flue gas have imposed various detrimental impacts on environment,and the development of deNO_(x) catalysts with low-cost and high performance is an urgent requirement.Iron oxide-based material has been explored for promising deNO_(x) catalysts.However,the unsatisfactory low-temperature activity limits their practical applications.In this study,a series of excellent low-temperature denitrification catalysts(Ha-FeO_(x)/yZS)were prepared by acid treatment of zinc slag,and the mass ratios of Fe to impure ions was regulated by adjusting the acid concentrations.Ha-FeO_(x)/yZS showed high denitrification performance(>90%)in the range of 180–300℃,and the optimal NO conversion and N2 selectivity were higher than 95%at 250℃.Among them,the Ha-FeO_(x)/2ZS synthesized with 2 mol/L HNO3 exhibited the widest temperature window(175–350℃).The excellent denitrification performance of Ha-FeO_(x)/yZS was mainly attributed to the strong interaction between Fe and impurity ions to inhibit the growth of crystals,making Ha-FeO_(x)/yZS with amorphous structure,nice fine particles,large specific surface area,more surface acid sites and high chemisorbed oxygen.The in-situ DRIFT experiments confirmed that the SCR reaction on the Ha-FeO_(x)/yZS followed both Langmuir-Hinshelwood(L-H)mechanism and Eley-Rideal(E-R)mechanism.The present work proposed a high value-added method for the preparation of cost-effective catalysts from zinc slag,which showed a promising application prospect in NO_(x) removal by selective catalytic reduction with ammonia.

Biphasic synergy catalysis and active sites of VMgO catalysts for oxida- tive dehydrogenation of propane

THE oxidative dehydrogenation of propane （ODP） to propene is one of the potentially important catalytic processes for the effective utilization of light alkanes. The VMgO catalysts which have better catalytic performances for the reaction have aroused much interest and argument.Kung et al. proposed that the active phase was magnesium orthovanadate （Mg3V2O8）, but Volta et al. suggested that magnesium pyrovanadate （α-Mg2V2O7） was the active phase; in this phase, V4+ ions which are associated to the formation of oxygen vacancies could stably exist, and Mg3V2O8 is responsible for the total oxidation due to nonexistence of V4+ ions.

Chemoselective synthesis and cytotoxic activity of a series of novel benzo[1,4]oxazin-3-one derivatives

That tetraacetonitrile copper perchlorate catalyzes intramolecular amidation of arenes was found to be a new strategy for construction of nitrogen-containing heterocycles and resulted in the formation of a series of novel benzo[1,4]oxazin-3-one derivatives from N-（1,3-diphenyl-1H-1,2,4-triazol-5-yl）-2-phenoxyacetamides.This approach of heterocyclic construction proceeds in a chemoselective manner in which only benzo[1,4]oxazin-3-one derivatives were obtained by C—N bonds formation with cheap and simple copper salt catalyst under mild conditions in moderate to good yields.The biological assay of some of benzo[1,4]oxazin-3-one derivatives showed that they had moderate antiproliferative activity toward MDA-MB231 and HeLa cancer cell lines.